Method and apparatus for making contact pins



E. L. STARR April 12, 1932.

Filed July 13, 1929 METHOD AND APPARATUS FOR MAKING CONTACT PINS IN V EN TOR. EVE/@f/L- Sir/9' w, m v

A TTORNEYS.

Patented Apr. 12, 1932 UNITED STATES;

PATENT OFFICE wan L. srnnrqor PROVIDENCE, RHODE. ISLAND, ASSIGNOB. ToFuLFoRD MFG.

00., or rnovrnnncn, RHODE ISLAND, A conroRArroN or nnonn ISLAND 'ME'I'HOD' AND APPARATUS F03. MA ING CONTACT 'rms Application filed. J l ia sae. Serial No. 378,032.

The presentinvention relates to anim proved method and apparatus for forming One object of the inventlon 1s tofacilitate the formation of tubular contact pins. I

' Another object is to reduce amount of man ual handling and the number of manufactur- 1o ing operations required.

A third object is to e the formed pin tothe-punch head of the forming machine. j 1 -Other' objects and advantageous features will be more readily apparent fromthede tailed description following, in conjunction with the accompanying drawings, and-will 1 lee-particularly pointed out in the; claims. In the drawings:

- Figure 1 is an elevatlon of the contactp'in,

- Figures 2 to 9 show steps in the formation of the contact pin;

Figure 10 shows the operative'elements of' the forming machine, with the pin in posi 7 tion for forming the flanged shoulder.

Figure 11 is a view showinglthe shape of the pin atthe end of the forming of theshoulder; and I i i V Figure 12 shows the completed pin as forced outwardly from the lowerdie of the forming machine.

v The blank is usually drawn up from sheet stock to form a series of cups progressively diminishing in diameter and increasing in length, the drawing operations 7 occurring successively in an eyelet machine until the required length and diameter are formed after which thecup is usually removed from; the eyelet machine and placed in a separate machine to form the folded flange thereon, as it is found when using a die toform' the flange in the eyelet machine that the pin will stick in the upper or head die because.

.this die has greater frictional engagement with the pin so that the same cannot readily be removed; thus necessitating further handling of the article beforefinishing' It is the purpose of this invention to so form the .die in which the flange is formed that this sticking in the head die will not occur, thus prevent sticking of:

shapes 21a, 21b, 21c, 21d-and 21e,;usually in a 7 follows V scription of the present embodiment of this inventionillustrating one .form of carrying out the same.

\ Referring to the drawings, the contact pin 1 20 is formed by drawing a blank 21 into the tubular form 22'shown in Fig.8, the blank belng successivelydrawn into the form or "in the lower die 28, which has acentral recess 29, tapered as shown, anda flange-form-. ing recess 30; a kick-out pin 31 is utilized as, the'base of the recess 29 and is reciprocated by a spring-pressed tappet 32 in response to the movements of the cam 33.

The formation of the completed pin is as r The blank 21 is successively shaped as shown in Figs. 2 to 8, and then positioned'between the lower die 28'and the punch die 23. Movement of the punch die towards the lower die causesthe contact pin to assume the form 20a shown in Fig. 11, with ,the' open end 7 rounded, the shoulder flange formed between the recesses 27 and 30, and the head tapered and enlarged as at 34 within the recess 29. The punch head 23 is then moved upwardly,

the pin remaining in the recess 29 because of V the tapered enlarged head, upward movement of thekick-out pin 31 now forces the pin out thru thesmall end of the recess 29 to make the head cylindrical by removing the taper, the pin dropping from the lower die into the receivingbasket. V

The improved method and apparatus therefore eliminate sticking of the formed pin to the punch head, the formed pin being positively retained in the lower die, from where it is forced out by the kick-out pin.

While I have described one specific embodiment of an apparatus for accomplishing the novel method, such changes in procedure or in structure may obviously be made, as are within the scope of the invention as defined in the appended claims.

Claims:

1. In a method of forming tubular contact pins between a base die and a movable punch die, the step of enlarging the pin within the positively retained in the base die upon withdrawing movement of the punch die and removing the pin from the base die after with drawing the punch die therefrom.

3. In a method of forming tubular contact pins between a base die and a reciprocable' punch die, the steps of spreading the pin in the base die to be positively locked in the base die upon withdrawing movement of the punch die, and then contracting the pin to eject it from the base die.

4. In a method of forming tubular contact pins between a base die and a reciprocable punch die, the steps of forming the pin with a taper converging towards the base die entrance so as to be positively retained in the base die upon withdrawing movement of the punch die,and ejecting the pin from the base die while removing the taper;

5. In a method of forming contact pins between two relatively movable dies, one of which has greater frictionalengagement with the formed pin than theother, the step of spreading the pin within a recess in a selected die to be positively retained therein upon separation of the dies and removing the pin from said die after separation of said dies.

6. In a method of'forming contact pins between two relatively movable dies, one of which has greater frictional engagement with the formed pin than the other, the step of spreading the pin in a selected die in a taper converging towards the opening thereof so as to be positively retained therein upon separation of the dies and forcing the pin from said 7 die after separation of said dies.

7. A base die for the formation of contact pins comprising a pin receiving recess having an enlargement therein greater than the entrance to said recess, said recess having a movable'base, said base being movable to eject a pin thru the entrance to said recess.

8. A base die for the formation of contact pins comprising a pin receiving recess having an enlargement therein greater thanthe entrance to said recess, said recess having a movable base, said base being movable to eject a pin thru the entrance to said recess, the sides of said recess receding from the entrance to form an enlargement.

9. A machine for forming contact pins comprising a base die, a pin receiving recess therein having an enlargement greater than the entrance to said recess, said recess havinga movable base, said base being movable to eject a pin thru the entrance to said recess and a cooperating punch die.

10. A machine forforming contact pins comprising a base die, a pin receiving recess therein, theends of said recess receding from the entrance to form an enlargement, said recess having a movable base, said base being movable to eject a pin thru the entrance to said recess and a cooperating punch die.

11. A- machine for forming contact pins comprising a base die for receiving the head of the" pin and having a recess therein, the sides of said recess receding from the entrance to forman. enlargement, a flangeforming recess adjacent the said entrance, and a punch die having a recess for receiving the body of thepin and a flange-forming recess cooperating with the flange-forming recess of the base die.

12. In a method of forming tubular elements between a base die and a: relatively elongated movable punch die, the step of changing the outerform of the element with in the 'base' die to aform different from that of the base die opening so as toclock the element in the base die against the frictional pull, exerted by the punch diexon its withdrawal movement and forcing the pin from Said base die after withdrawal of the punch 13. .Ina method of forming tubular elements between a base die and a relatively elongated movable punch die,-,the ste of spreading the element within the base die to be larger than the base die opening so as to lock the element in the base die against the frictional pull exerted by the punch die on its withdrawal movement'and forcing the pin from said base die after withdrawal of the punch diei u i I 14. In a method of forming tubular elements between a basedie 'and'a relatively elongated movable punch die, the steps of changing the outer form of the element within'the base die to a form differing from that of the base die opening so as to lock the element in the base die against the frictional pull exerted by the punch die on its withdrawal movement, and then changing the outer'form to conform to that of the base die opening for ejection of the element from the base die. a Y

'15. In a method of forming tubular elements between a base die and a relatively elongated movable punch die, the steps of spreading the element within the base die to be larger than the base die opening so as to lock the element in the base die against the frictional pull exerted by the punch die on its Withdrawal movement, and then constrict ing the element to conform to the base die opening for ejection of the element from the base die.

In testimony whereof I aflix my signature.-

EVERETT L. STARR. 

